The purpose of the proposed research is to associate childhood obsesity with earlier eating and physical activity practices and parental attitudes, and to earlier body measurements. The subjects will be children, now 9 years old, who have been followed since age 6 months in a longitudinal study of growth and body composition. Data collected at ages 6 months, 1, 2, 3, 4, 5, 6, and 8-3/4 years include dietary; physical activity; parents' beliefs and opinions about eating practices, child feeding, physical activity, and fatness/leanness of their children; and anthropometry including height, weight, 4 skinfolds, and 4 circumferences. At 8-3/4 years body density was determined by underwater weighing. The proposed research will focus on similar data for 6 years as the children enter puberty and until adolescent growth has passed its peak at age 16 years. The usefulness of selected data for predicting obesity will be determined. Critical periods for obesity development will be identified. Longitudinal patterns of diet, physical activity, body measurements, growth and socio-cultural factors will be analyzed in relation to fatness/leanness.